Earlier:
OK, there must be a fair few properties you can change… but should be straight forward right?
You made my day 
Ahahahahahaha +1
Yep it’s a bit difficult at the moment hehe 
Epic has said they plan to split it up in a future release, for now it’s not so simple though.
It doesn’t mean much now, but you CAN click on that struct and start deselecting the pins you don’t need.
Unfortunately, there’s no simple option for “hide all” (or "hide all except " or whatever) but once you get the struct into that state, you CAN copy-paste it for later use so in the future you can check just what you need.
Be aware, though, that when you Set a postprocess setting, it needs to have ALL the elements of your desired postprocess, not just the ones you’re changing in BP. So for example, if you want to dynamically alter the amount of motion blur in BP when you sprint, you still need to include the AO, Postprocess materials, HDR, bloom, and whatever else you use by default when you Set your postprocess settings. Otherwise you’ll dynamically create a new postprocess settings with your desired motion blur and nothing else (for example).
Which unfortunately means you may need quite a few of those pins after all.